1. Field of the Invention
This application relates generally to a bar clamp and, more specifically, to a bar clamp with an integrated caul for promoting uniformly-aligned boards during edge glued together.
2. Description of Related Art
Furniture cases, tabletops and other large pieces of furniture are typically fabricated from wide panels. Early on, old-growth trees having large diameters allowed such panels to be milled as a single piece. But now that most of the old-growth trees have been cut down such trees are becoming increasingly rare, meaning single panels that are suitably-wide to individually form a tabletop or other large piece of furniture are either unavailable or cost prohibitive.
To satisfy the demand for tabletops and other large furniture formed from wide panels, a plurality of relatively-narrow boards are edge glued together in a side-by-side arrangement. Glue or another suitable adhesive is applied to one or both edges of contiguous boards, which are disposed between opposite jaws of a clamp. At least one of the clamp jaws is urged toward the other jaw, thereby tightly pressing the edges of those contiguous boards together while the glue dries. However, many edge-aligned boards may be clamped between the opposing jaws. Under pressure, a rail of a conventional clamp may deflect enough to cause the edge-aligned boards to bow, creating an unwanted arc in the finished assembly. Further, the wet glue or other adhesive applied between the joined edges of the contiguous boards can initially act as a lubricant, possibly allowing the edge-aligned boards to slip relative to each other when subjected to sufficient pressure.
Several attempts have been made to keep edge-aligned boards being glued together in a linear, planar arrangement. One method of keeping such boards in alignment involved gluing sacrificial boards transversely across the edge-aligned boards that are being glued together between the jaws of a clamp to form the tabletop or other wide panel that will form part of the end product. Once the glue has dried, the region of the assembly including the sacrificial boards is cut off and discarded. Such a process, however, is wasteful and time and labor intensive, requiring several additional construction steps to produce the wide panel. Moreover, since wood scraps are often used for the sacrificial boards that will eventually be discarded, the sacrificial boards may not themselves be planar, again allowing the edge-aligned boards to bow.
Another proposed solution to clamping edge-aligned boards involves the use of wall-mounted panel clamps. Such clamps include one rail that is bolted or otherwise coupled to a wall, for example. A jaw attached to this rail supports the edge-aligned boards between the rail affixed to the wall and another, opposing rail that is bolted to the rail affixed to the wall to sandwich the edge-aligned boards. A force can then be applied to urge the edge-aligned boards together while glue between the boards dries. However, such a wall-mounted solution is an expensive, permanent installation that is dedicated solely for the purpose of edge-gluing boards into wide panels. Such wall-mounted solutions also require a large amount of free space to be fixed in place, and are not transportable by hand for use in other types of clamping operations at other locations.